package thread;

public class Demo15 {
    private static Object locker = new Object();
    public static void fun1() {
        synchronized (locker){
            fun2();
        }
    }
    public static void fun2() {
        fun3();
    }
    public static void fun3() {
        fun4();
    }
    public static void fun4() {
        synchronized (locker) {
        }
    }
    public static void main(String[] args) {

    }
}
